JPH0127099Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an automatic pipettor used for dispensing and diluting samples.

Conventionally, an automatic pipetting dilutor (Pipettor-Dilutor) manufactured by Carvo Scientific Instruments Inc. in the United States has been known as this type of automatic pipettor. This includes a reagent syringe, a three-way valve provided at its tip, a reagent tube that communicates with the reagent syringe at one position of the three-way valve, and a reagent tube that communicates with the reagent syringe at another position of the three-way valve. The reagent is inhaled through the reagent tube through the reagent syringe, the sample is inhaled through the nozzle through the sample syringe, and the three-way valve is switched to release the sample from the nozzle. The sample and reagent are each discharged in sequence, and predetermined amounts of the sample and reagent are dispensed and mixed.

However, in the conventional automatic pipettor as described above, it was necessary to keep the desired amount of sample or reagent below the full capacity of the sample syringe or reagent syringe, respectively. On the other hand, if a large-volume syringe is installed and the desired volume is small, the syringe must be replaced with a smaller-capacity one from a precision point of view. It was very difficult to handle as it had to be replaced. Moreover, if the seal is replaced frequently, the life of the seal will be shortened, and liquid leakage will likely occur. Furthermore, large-capacity syringes have large dynamic friction, so a powerful drive mechanism is required, resulting in an expensive device.

This invention solves the above problem by improving the ability to aspirate and dispense the sample or reagent without changing the syringe even when the desired amount of sample or reagent is larger than the full capacity of the sample syringe or reagent syringe. The purpose of this invention is to provide an automatic pipettor which is characterized by a comparison between a set desired sample volume or reagent volume and the full volume of the sample or reagent syringe, respectively. means, when the desired amount is larger than the full capacity, the syringe is driven to inhale and eject multiple times, and when the sum of the inhaled amounts up to that point during the inhalation drive reaches the set value, the inhalation is stopped and the syringe is ejected; The present invention is provided with a control means for driving and then stopping, and a notification means for notifying that the final ejection has been completed.

The comparison means and control means are, for example, microcomputers.

This invention will be explained in detail below based on the embodiment shown in the drawings. Note that this invention is not limited to this.

Reference numeral 20 shown in FIG. 1 is an embodiment of the automatic pipettor of this invention. Plunger 2 of reagent syringe 1 and plunger 4 of sample syringe 3
These are pulley wire type plunger drive devices 9 and 10 driven by pulse motors, each driven under the control of a microcomputer 11. The three-way valve 7 provided at the tip of the reagent syringe 1 is a direct-acting solenoid valve, and is normally located at a flow path position (solid line) that communicates the reagent syringe 1 and the reagent tube 8. While energized, the flow path position (broken line) is switched to allow the reagent syringe 1 to communicate with the nozzle 5. The switching response time is approximately 3 msec. This three-way valve 7 is also under the control of the microcomputer 11. In addition, 6 is a three-way flow path, 12 is a buzzer, and 13 is an operation console.

Next, I will explain the operation, but the full capacity of reagent syringe 1 is 1 ml, and the full capacity of sample syringe 3 is
It shall be 100μ.

First, a desired sample amount and reagent amount are input and set from the operation console 13. For example, if the sample amount is 50μ,
Enter the reagent volume as 2.5ml.

Next, a "suction" start command is input from the console 13. Then, microcomputer 1
1 divides the set desired sample amount of 50 μ by the full capacity of the sample syringe 3 of 100 μ, and determines the stroke of the plunger 4 to be 1/2 of the full stroke from the quotient of 0.5. Also, divide the set desired reagent volume of 2.5 ml by the full volume of the reagent syringe 1, 1 ml, and since the quotient of 2.5 is greater than 1, it is recognized that the desired volume is larger than the full volume, and the plunger 2 is stroked. is determined to be two full strokes and one half of the full stroke. Then, as shown in Fig. 2, the plunger 4
1/2 of the full stroke, the plunger 2 is driven in the full stroke suction direction, that is, in the downward direction, and then stopped.

When a "discharge" start command is input from the console 13, the microcomputer 11 energizes the three-way valve 7 to switch the flow path to the nozzle 5 side, and first moves the plunger 2 located further downward in the discharge direction. That is, it is driven upward. Then, when the position of the plunger 2 is aligned with the position of the plunger 4, the plunger 4 is also driven in the discharge direction, and stops after complete discharge. At this point, the set amount of sample has been dispensed, but there is still 1 ml of reagent.
The buzzer 12 is activated briefly twice to notify the operator that the plunger 2 will continue to be driven. Thereafter, as shown in Fig. 2, the three-way valve 7 is switched, the plunger 2 is driven, and the buzzer 12 is activated, 1 ml of reagent is aspirated and discharged, and finally 0.5 ml of reagent is pumped out.
ml is aspirated, dispensed, and stopped, and the buzzer 12 is activated once longer to notify the operator that the last dispense has been completed.

In this way, 2.5 ml of reagent has been dispensed, but if you want to know the progress during the process, please use the operation console.
For example, if 3 is equipped with several digits of 7 segment LEDs,
It may be possible to display the cumulative amount of reagent that has already been dispensed, or to display how many more suction and discharge drives must be performed.

In the above example, the case where the desired amount of reagent is larger than the full capacity of the reagent syringe is described, but the operation is almost the same when the desired amount of sample is larger than the full capacity of the sample syringe. This can be easily understood from the above embodiments. Therefore, the explanation regarding this will be omitted.

As explained above, according to the automatic pipettor of this invention, a large volume of sample or reagent can be inhaled and discharged without replacing the syringe simply by being equipped with a small volume syringe. Therefore, there is no need to change the syringe as in the past, which is extremely convenient in practice. Also, since there is no need to replace the syringe, the life of the seal is extended. Furthermore, since there is no need to drive a large-capacity syringe, an inexpensive drive mechanism can be used, which is economical.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the construction of one embodiment of the automatic pipettor of this invention, and FIG. 2 is a time chart of the operation of the automatic pipettor shown in FIG. 1. 1... Reagent syringe, 2... Reagent syringe plunger, 3... Sample syringe, 4...
Sample syringe plunger, 5...nozzle,
7... Three-way valve, 8... Reagent tube, 9, 10...
... plunger drive device, 12 ... microcomputer, 20 ... automatic pipettor.

Claims (1)

[Claim for Utility Model Registration] During inhalation, the three-way valve provided at the tip of the reagent syringe is switched to the reagent tube side, and the reagent is inhaled into the reagent syringe through the reagent tube, and the sample is injected through the nozzle. In an automatic pipettor that aspirates a sample using a syringe and, when dispensing, switches the three-way valve to the nozzle side and automatically dispenses the aspirated sample and reagent from the nozzle in this order, the set desired sample amount or Comparison means for comparing the reagent amount and the full capacity of the sample or reagent syringe, and when the desired amount is larger than the full capacity, the syringe is driven to inhale and eject multiple times, and the previous inhalation is performed during the inhalation drive. An automatic pipettor characterized by comprising a control means for stopping suction and driving for ejection when the total amount reaches the set value, and a notification means for notifying that the final ejection has been completed.